Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Laser Fired Low Emission Futuristic Internal Combustion Engines Presented by Dhananjay Kumar Srivastava Research Scholar Engine Research Laboratory Department of Mechanical Engineering Indian Institute of Technology Kanpur Kanpur

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Source: D.K. Srivastava et al. 13th International symposium on power electronics, 2005

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Introduction Paper #  As a matter of fact, excellent efficiencies of internal combustion engines -in the first place of gas engines- of presently close to 46%.  This requires remarkable technical improvements in general, and especially with respect to the ignition system employed. Increase of spark plug voltage versus rising break mean effective pressure BMEP Breakdown voltage of the spark plugs of a large gas engine depending on the test duration at two different BMEP levels Source: D.K. Srivastava et al. Proc. SPIE Vol. 6053, ,Jun. 9, 2006

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Potential Future Ignition System Homogeneous Charge Compression Ignition (HCCI) Diesel pilot ignition Laser ignition

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 NO x Emission Potentials spark ignition laser ignition NO X [mg/Nm³] diesel pilot ignition direct pre chamber direct pre chamber Source: D.K. Srivastava et al. Proc. SPIE Vol. 6053, ,Jun. 9, 2006

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Laser Ignition  An alternative solution to standard spark plug is the use of pulsed laser, focused to create plasma, representing the laser ignition.  Laser ignition, or laser-induced ignition, is the process of starting combustion by the stimulus of a laser light source.  Spark creation due to the local deposition of energy  Ignition itself based on a positive balance between the deposited energy and the losses

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 mixture burning focused laser beam plasma I>I threshold flame kernel E>E ignition laser beam convex lens Principle of Laser Ignition

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Advantages of Laser Ignition  Arbitrary positioning of the ignition plasma  Absence of quenching effects  Absence of erosion effects  Precise ignition timing  Simpler regulation of the ignition energy  Easy possibility of multipoint ignition

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Challenges  Propagation of laser pulse through fiber optics  Develope of a compact, robust and economic laser source  Durability of windows

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Design of Combustion Chamber

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Various stages of plasma growth 6 ns 7 ns 8 ns 9 ns 10 ns 11 ns 12 ns 13 ns 14 ns 15 ns 16 ns 18 ns 20 ns 22 ns 25 ns 30 ns 35 ns 40 ns 45 ns 50 ns 60 ns 70 ns 80 ns

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Video of Plasma Growth Source: D.K. Srivastava et al. SAE Paper no , New Delhi.

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Minimum Laser Pulse Energy Laser energy, required to ignite mixture, decreases with increasing pressure of chamber Source: M. Weinrotter et al. International J H. E. 30 (2005) 319 – 326

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Pressure History in Combustion Chamber λ = 2.5, laser λ = 3.0, laser λ = 3.5, spark plug λ = 3.5, laser λ = 3.0, spark plug λ = 2.5, spark plug Source: D.K. Srivastava et al. SAE Paper no , New Delhi.

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Direct comparison laser ignition – spark plug ignition Source: M. Weinrotter et al. SAE For 100% ignition reliability at 30 bar A/F rel = 2.05 (laser ignition) A/F rel = 1.74 (spark ignition)

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Laser Arrangement with Respect to Engine Pumping Source ECU Shaft Encoder Laser ECU Shaft Encoder Laser Adaptor Optical Fiber one laser for all cylinder system laser per cylinder system

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Conclusions  Plasma propagates towards the incoming laser beam  Plasma had the maximum emission peak 30 ns after the laser was fired and laser plasma UV-emission persisted for about 80 ns  Minimum laser pulse energy (MPE) for ignition is decreases with increasing initial pressure  The time of pressure rise in case of laser ignition is shorter than the spark ignition

Engine Research Laboratory Department of Mechanical Engineering, IIT Kanpur IITK REACH Symposium 2008 Thanks for Your Attention